Twenty-seven viruses including Zika, Ebola, Marburg, Lassa fever, chikungunya, mumps, Epstein-Barr and chicken pox are found in semen. The list is in addition to the obvious culprits such as hepatitis viruses, herpes viruses and HIV.

The vaccine induces antibodies against three different parts
of the virus, including two components that normally help herpes virus evade
immune attack. The findings are likely to lead to human clinical trials.

Around 1 in 10 men and 1 in 20 women reported sex with a new
partner during their travels abroad. Sex while overseas is less likely to be
protected. Use of alcohol and drug prevents adoption of safer-sex practices.